Roll forming machine



5, 1967 HIROSHI UTASHIRO ETAL. 3,355,922

ROLL FORMING MACHINE Filed Sept. 28, 1965 2 Sheets-Sheet 1 1967 HIROSHIUTASHIRO ETAL 3,355,922

ROLL FORMING MACHINE Filed Sept. 28, 1965 2 Sheets-Sheet 2 United StatesPatent 3,355,922 ROLL FORMING MACHINE Hiroshi Utashiro and Kenji Ohno,Tokyo, Japan, assignors to Kawasaki Steel Corporation, Kohe-shi,Hyogo-ken,

The present invention relates to a machine for continuously forming afiat metal sheet or band into a desired shape by passing the bandthrough successive rolling stations at each of which the band isprogressively deformed. More particularly, the present invention relatesto an improvement in a roll forming machine, wherein deforming rollerelements at one or more of the rolling stations are relatively inclined.

Roll forming machines are well known and have been used extensively foreffecting transverse bending of a flat strip or band of metal into adesired shape. Normally, the strip is passed successively through aplurality of rolling stations at each of which two or more rollers areemployed to progressively deform the strip. The number of stations andthe number of rollers at each station are normally determined by suchconsiderations as the type and thickness of the material being rolledand the complexity or the number and degree of transverse bends orcorners desired in the final product.

Normally, when it is desired to form a conventional rolled structuralelement, such as one of U-shaped crosssectional design, each rollingstation comprises a pair of co-acting upper and lower rollers which aremounted on parallel spaced shafts, the shafts at one or all of thestations being powered to convey the strip through the machine. Thelower or back-up roller is conventionally formed with a centralcylindrical drum portion and a pair of conical, enlarged end portions;the surfaces of the drum and end portions acting to define corners towhich a strip being rolled is to be conformed. The upper or deformingroller is conventionally formed with a central cylindrical drum portionand a pair of inwardly tapered end portions, which portions are normallydisposed parallel to the respective portions of the lower roller and arespaced therefrom a distance determined by the thickness of the stripbeing rolled.

In successive stations the axial length of the cylindrical drum portionsand the number and/or the relative inclination of the end portions ofthe upper and lower rollers are progressively varied to form thestructural member with the desired number of transverse bends orcorners. Normally one or more of the stations adjacent the end of themachine are employed to insure that the bends or corners of thestructural element are sharp or possess a prescribed roundness.

It has been found that after extended operation the sharp angledintersections or deforming surface portions defined by the drum and endportions of the upper or deforming roller are progressively worn away,whereby the corners of the structural element are formed with aprogressively larger radius of curvature than is desired. Since thewearing away of the upper roller is progressive, the customary periodicreplacement of such rollers does not result in a uniform product.

A further disadvantage of conventional roll forming machines arises whenthe intersections or forming surface portions of the deforming rollerwear unevenly or experience swaying defacement about the periphery ofthe roller. This results in successive variations in the radius ofcurvature of the corner of the structural element longitudinallythereof. In conventional machines, when roller wear of this natureoccurs, there is no alternative but to replace the roller.

Patented Dec. 5, 1967 It is therefore an object of the present inventionto provide an improvement in conventional roll forming machines, wherebysharp angle bends of a given radius of curvature may be continuouslyformed in a strip being rolled even through the deforming surfaceportion of the upper roller or rollers is uniformly worn away or swayingdefacement of the roller arises.

It is a specific object of the present invention to provide in a rollforming station having parallel spaced shafts and a lower or back-uproller disposed on one of the shafts, the improvement which includes theprovision of a bearing on the other shaft which permits a deformingroller element carried thereon to be selectively tilted with respect tothe axis of the shafts, whereby a corner of the strip being rolled maybe subjected to components of compressive force both normal and parallelto the axis of the shafts to ensure a desired degree of curvature.

A further object of the present invention is to provide in a rollforming station having a pair of parallel shafts and a lower or back-uproller carried on one of the shafts, the improvement which includes theprovision of a pair of spherical hearings on the other shaft whichpermit deforming roller elements carried thereto to be progressivelytil-ted to compensate for wear thereof and to thus ensure a desiredradius of curvature of the corners of the strip being rolled withoutexerting unbalanced forces axially of the shafts.

A still further object of the present invention is to provide animprovement in a roll forming machine wherein spherical bearings,provided on a driven shaft, are adapted to transmit rotary motion of theshaft to deforming roller elements carried on the bearings whilepermitting the roller elements to be tilted with respect to the axis ofthe shaft.

Other objects and features of the present invention will become apparentfrom the following description taken in connection With the accompanyingdrawings in which:

FIG. 1 is a front elevational view of a rolling station having portionsbroken away to illustrate the improvement of the present invention, andshowing one embodiment of the spherical bearing employed;

FIG. 2 is a fragmentary enlarged. view showing an upper forming rollelement in engagement with a corner of a strip being rolled;

FIG. 3 is a sectional view taken generally along the line 3-3 of FIG. 1,but showing an alternative and preferred structure of spherical bearingemployed in the practice of the present invention; and

FIG. 4 is a sectional view taken generally along the line 44 of FIG. 3.

In FIG. 1, there is illustrated a roll forming station, generally shownas 1, which incorporates the improvement of the present invention.Station 1 includes conventional structure in the form of a pair ofsupport columns or standards 2 and 3, which are employed to rotatablysupport a pair of parallel spaced apart shafts 4 and 5 by means ofsuitable bearings, not shown. Depending upon which embodiment of theimprovement of the present invention is to be employed, shafts 4 and 5may be braked or positively driven by suitable gearing, not shown. Aconventional lower or back-up roller, generally shown as 6, is providedon shafts 5 and is suitably keyed for rotation therewith by suitablemeans not shown. Roller 6 is maintained in predetermined spacing withrespect to columns 2 and 3 by means of cylindrical spacing elements 7and 8. Roller 6 comprises a cylindrical drum portion 9 and a pair offrusto-conical end portions 10 and 11 which co-act to define corners 12to which a strip 13, continuously fed through station 1, is to beconformed. Suitable means carried by columns 2 and 3, such as adjustmentscrews, not shown, are employed to control the distance between shafts 4and 5, and thus the pressure applied to sheet 13 passing between back-uproller 6 and the upper roller assembly, which is generally indicated as14, and forms the improvement of the present invention. While backuproller 6 is illustrated as being one piece construction, it will beapparent that in some instances it may be desirable to divide the rollerin the area of drum portion 9 and to space apart the thus formed halvesof the roller by suitable means similar to spacers 7 and 8.

The upper roller assembly 14 includes a pair of deforming rollerelements 15 and 16, which are supported on spherical bearings, generallyshown as 17 and 18; the bearings being spaced axially of shaft 4 andhaving their centers placed at 19 and 20, respectively. As will be seenby referring to FIG. 1, bearings 17 and 18, and thus centers of rotation19 and 20, are selectively positioned with respect to the corners 12 ofroller 6 and with respect to each other by removable cylindrical spacers21, 22 and 23, respectively.

In the first embodiment of the present invention, generally illustratedin FIG. 1, deforming roller elements 15 and 16 are frictionally drivenby surface contact with strip 13; the bearings 17 and 1S permitting theroller elements to freely rotate relative to shaft 4, which if desiredmay idle or be braked against rotation by means, not shown. In thesecond and preferred embodiment, generally illustrated in FIGS. 3 and 4,deforming roller elements 15 and 16 are positively driven by shaft 4acting through bearings 17 and 18. Generally it is desirable topositively drive the strip being rolled by positively driving thedeforming roller lements to prevent buckling of the strip immediatelybefore the station. Also, positive driving of the deforming rollerelements insures that the peripheral speed of such roller elements maymore evenly be matched with the speed of the strip to retard swayingdefacement of the roller elements.

In both embodiments of the present invention, bearings 17 and 18 eachinclude an inner part 24, which is affixed for rotation with shaft 4 bymeans of key 25 received within slots 26 and 27 provided in shaft 4 andinner part 24, respectively, and an outer part 28, which is affixed forrotation with roller elements 15 or 16 by means of key 29 receivedwithin slots 30 and 31 provided in outer part 28 and roller elements 15and 16, respectively. Both the inner parts 24 and outer parts 28 areprovided with coacting peripheral surface portions 32 and 33,respectively. Bearings 17 and 18 may be assembled in any desired manner,as for instance by forming outer part 28 in two parts which are joinedby bolts or welding.

As will be seen by referring to FIGS. 1 and 4, roller elements 15 and 16are each provided with bore openings 34 and 35, respectively, to receiveouter bearing parts 28. Parts 28 are retained within bore openings 34and 35 by means of annular bearing covers 36 and 37 which are removablyaffixed to roller elements 15 and 16 by means of threaded bolts 38. Thisconstruction permits the roller elements when Worn beyond use to beremoved from bearings 17 and 18 without disturbing the positioning ofthe hearings on shaft 4.

In the first embodiment of the present invention, spherical surfaceportions 32 and 33 permit universal motion of bearing parts 24 and 28,and thus both relative rotatable and tilting motion of roller elements15 and 16 with respect to the axis of shaft 4 about centers 19 and 20.

In the second and preferred embodiment of the present invention keymeans, generally indicated as 39, are provided to lock inner parts 24and outer parts 28, and thus roller elements 15 and 16, for rotationwith shaft 4, while permitting roller elements 15 and 16 to be tiltedwith respect to the axis of shaft 4 about centers 19 and 20, as showngenerally in FIG. 1. Key means 39 includes a slot 40 provided in thespherical surface portions 32 of inner parts 24, a conical orhemispherical recess 41 provided in the spherical surface portions 33 ofouter parts 28, and a ball bearing 42. Ball bearing 42 is received forrelative rotary movement within recess 41 and for relative rotary andsliding movement within slot 40. It will be appreciated that thepositioning of slot 40 and recess 41 on parts 24 and 28 may be reversedif desired.

As shown in the drawings, roller elements 15 and 16 are provided,respectively, with annular peripheral deforming surface portions 43 and44 which co-act with the back-up roller 6 to deform sheet 13 in the areaof corners 12. Roller elements 15 and 16 are also provided withoppositely and inwardly inclined surface portions 45 and 46, which bounddeforming surface portions 43 and 44, respectively. It has been founddesirable to incline surface portions 45 and 46 with respect to portions9, 10 and 11 of back-up roller 6 at an angle B, which is equal to theangle A at which roller elements 15 and 16 are tilted with respect tothe axis of shaft 4. Angle A is desirably limited to between 5 and 15 Insetting up the present invention in a roll forming station, bearings 17and 18 are placed on shaft 4 and a spacer 23 of suflicient length ischosen to space centers 19 and 20 a distance apart, which will permitroller elements 15 and 16 to tilt from between 5 and 15 degrees withrespect to the axis of shaft 4 when deforming surface portions 43 and 44engage strip 13 in the areas of corners 12, the latter being spaced apredetermined distance apart W. Preferably, centers 19 and 20 are spacedequi-distant from and on opposite sides of a plane drawn equi-distantfrom corners 12 to prevent unbalance forces axially of the shafts.

It will be apparent that when shaft 4 is forced toward shaft 5, as bysuitable adjustment screws, the roller elements 15 and 16 are forcedapart as illustrated in FIG. 1, thereby deforming surface portions 43and 44 exert a compressive force on strip 13 in the area of corners 12,the force having components both normal and parallel to the axis ofshafts 4 and 5. As will also be apparent, the relative axial placementof centers 19 and 20 with respect to corners 12 determines the magnitudeof the individual force components.

Accordingly, it will be seen that as abrasion of deforming surfaces 43and 44 proceeds the points or surfaces at which the roller elements 15and 16 engage strip 13 are forced outwardly against the corners 12,whereby the sharpness or degree of roundness of the strip corner is notchanged and the life of the roller elements is prolonged. Also, it willbe apparent that by positively forcing the roller elements outwardly anyswaying defacement Evhich may arise on the roller elements iscompensated The number of stations in the roll forming machine at whichthe improvement of the present invention is employed and the placementof such stations will normally be determined by the desiredcross-sectional design to which the strip is to be formed and thethickness of the strip being formed. However, in a conventional eightstation machine employed to form U-shaped or box channel structuralmembers, normally one station employing the improvement is provided andsuch station placed in 6th of 7th station position. In twenty or morestation machines, normally stations thirteen to sixteen are providedwith the improvement of the present invention.

While the improvement of the present invention has been illustrated anddescribed as including a pair of spherical bearings, which are axiallyspaced from each other and disposed in a prescribed relationship withrespect to a pair of corners formed on a back-up roller, and a pair ofdeforming roller elements carried one on each of the spherical bearings,it will be appreciated that the improvement may include only onespherical hearing, it will be appreciated that the improvement mayinclude only one spherical bearing-roller element assembly or a grouphaving three or more of such assemblies, depending on the number ofcorners to be formed in the strip being rolled. Further, in cases wherethe angles of the several corners to be formed or the thickness of theportions of the strip being rolled adjacent to the corners varies, thespacing between the respective spherical bearings and theircorresponding corners may be varied. Thus, since these and othermodifications of the improvement of the present invention may occur topersons skilled in the art in view of the present disclosure, we wishour protection to be limited only by the scope of the appended claims.

What is claimed is:

1. In a roll forming machine including at least one rolling stationhaving parallel spaced apart shafts and roller means carried on one ofsaid shafts, said roller means having a plurality of relatively inclinedsurface portions adapted to define at least one corner to which a stripbeing rolled is to be conformed, the improvement which comprises atleast one bearing means carried on the other of said shafts and a rollerelement carried one on each of said bearing means, said roller elementhaving a deforming surface portion adapted to coact with said corner toeffect deformation of a strip being rolled, said bearing meanspermitting said roller element to be tilted with respect to the axis ofsaid other shaft, whereby upon the forcing together of said shafts saiddeforming surface portion is adapted to exert a compressive force on astrip being rolled in the area of said corner, said force havingcomponents both parallel and normal to the axes of said shafts.

2. The roll forming machine of claim 1 wherein said bearing meansincludes a first part keyed for rotation with said other shaft and asecond part keyed for rotation with said roller element, said partshaving cooperating spherical surface portions to permit relative slidingmovement of said parts and, said roller element is driven by frictionalengagement with a strip being rolled.

3. The roll forming machine of claim 1 wherein said other shaft ispowered and said bearing means is adapted to transmit motion of saidother shaft to said roller element.

4. The roll forming machine of claim 3 wherein said bearing includes afirst part keyed for rotation with said other shaft, a second part keyedfor rotation with said roller element, said parts having cooperatingspherical surface portions, and means to key said parts together forsimultaneous rotational movement about the axis of said other shaft,said key means permitting relative sliding movement of said partswhereby said roller element may be tilted with respect to the axis ofsaid other shaft.

5. The roll forming machine of claim 4 wherein said key means includes aslot provided in the spherical surface portion of one of said parts, arecess provided in the spherical surface portion of the other of saidparts, and a ball bearing, said ball bearing being received for relativerotational movement within said recess and received for relativerotational and sliding movement within said slot.

6. In a roll forming machine including at least one rolling stationhaving parallel spaced apart shafts and roller means carried on one ofsaid shafts, said roller means having relatively inclined surfaceportions adapted to define spaced corners to which a strip being rolledis to be conformed, the improvement which comprises a plurality ofbearings carried on and spaced axially of the other of said shafts and aplurality of roller elements carried one on each of said bearings, eachof said roller elements having a deforming surface portion adapted tocoact with one of said corners to effect deformation of a strip beingrolled, said bearings permitting said roller elements to be inclinedwith respect to the axis of said other shaft, whereby upon the forcingtogether of said shafts the deforming surface portions of said rollerelements are adapted to exert compressiveforces on a strip being rolledin the area of said corners, said forces having components both paralleland normal to the axes of said shafts.

7. The improvement in a roll forming machine according to claim 6,wherein means are provided to selectively position said bearings axiallywith respect to each other and said bearings axially with respect tosaid corners on said roller means.

8. In a roll forming machine including at least one rolling stationhaving parallel spaced apart shafts and a contoured roller carried onone of said shafts, said contoured roller having relatively inclinedsurface portions adapted to define a pair of corners to which a stripbeing rolled is to be conformed, the improvement which comprises a pairof bearings carried on and spaced axially of the other of said shafts,the distance between said bearings being less than the distance betweensaid corners on said contoured roller and said bearings being disposedequidistant from and on opposite sides of a plane drawn equidistant fromsaid corners, and a pair of roller elements carried one on each of saidbearings, each of said roller elements having an annular peripheraldeforming surface portion adapted to co-act with one of said corners toeffect deformation of a strip being rolled, said bearings permittingsaid roller elements to be tilted in opposite directions with respect tothe axis of said other shaft, whereby upon the forcing together of saidshafts the deforming surface portions of said roller elements areadapted to exert compressive forces on a strip being rolled in the areasof said corners, said forces having components both parallel and normalto the axis of said shafts and said parallel components being equal andopposite.

9. The improvement in a roll forming machine according to claim 8wherein said roller elements are tilted at an angle of from between 5and 15 degreeos with respect to the axis of said other shaft.

10. The improvement in a roll forming machine according to claim 9wherein said deforming surface portion of each roller element is boundedby annular radially inwardly and oppositely inclined surface portions,said inclined surface portions of said roller elements being inclinedwith respect to said corner defining inclined surface portions of saidcontoured roller at an angle corresponding to the angle at which saidroller elements are tilted.

11. In a roll forming machine including at least one rolling stationhaving parallel spaced apart shafts and a contoured roller carried onone of said shafts, said contoured roller having relatively inclindedsurface portions adapted to define spaced corners to which a strip beingrolled is to be conformed, the improvement which comprises a pair ofspherical bearings carried on and spaced axially of the other of saidshafts, the distance between said bearings being less than the distancebetween said corners on said contoured roller, and a pair of rollerelements carried one on each of said bearings, each of said rollerelements having a deforming surface portion adapted to coact with one ofsaid corners to effect the deformation of a strip being rolled, saidbearings permitting said roller elements to be tilted in oppositedirections with respect to the axis of said other shaft, whereby uponthe forcing together of said shafts the deforming surface portions ofsaid roller elements are adapted to exert compressive forces on a stripbeing rolled in the area of said corners, said forces having componentsboth parallel and normal to the axis of said shafts.

12. The improvement in a roll forming machine according to claim 11,wherein said bearings are disposed equi-distant from and on oppositesides of a plane drawn equi-distant from said corners.

13. The improvement in a roller forming machine according to claim 12,wherein means are provided to vary the distance between said bearings.

14. The improvement in a roll forming machine according to claim 12,wherein said other shaft is powered and said bearings are adapted totransmit motion of said other shaft to said roller elements, and eachsaid bearing includes a first part keyed for rotation with said othershaft, a second part keyed for rotation with said roller element, saidparts having cooperating spherical surface portions, and means to keysaid parts together for simultaneous rotational movement about the axisof said other shaft, said key means including a slot provided in thespherical surface portion of one of said parts, a recess provided in thespherical surface portion of the other of said parts, and a ball bearingbeing received for relative rotational movement Within said recess andfor relative rotational and sliding movement within said slot.

References Cited UNITED STATES PATENTS 2,352,675 7/1944 Yoder 7Z181CHARLES W. LANHAM, Primary Examiner.

R. D. GREFE, Examiner.

1. IN A ROLL FORMING MACHINE INCLUDING AT LEAST ONE ROLLING STATIONHAVING PARALLEL SPACED APART SHAFTS AND ROLLER MEANS CARRIED ON ONE OFSAID SHAFTS, SAID ROLLER MEANS HAVING A PLURALITY OF RELATIVELY INCLINEDSURFACE PORTIONS ADAPTED TO DEFINE AT LEAST ONE CORNER TO WHICH A STRIPBEING ROLLED IS TO BE CONFORMED, THE IMPROVEMENT WHICH COMPRISES ATLEAST ONE BEARING MEANS CARRIED ON THE OTHER OF SAID SHAFTS AND A ROLLERELEMENT CARRIED ONE ON EACH OF SAID BEARING MEANS, SAID ROLLER ELEMENTHAVING A DEFORMING SURFACE PORTON ADAPTED TO COACT WITH SAID CORNER TOEFFECT DEFORMATION OF A STRIP BEING ROLLED, SAID BEARING MEANSPERMITTING SAID ROLLER ELEMENT TO BE TILTED WITH RESPECT TO THE AXIS OFSAID OTHER SHAFT, WHEREBY UPON THE FORCING TOGETHER OF SAID SHAFT SAIDDEFORMING SURFACE PORTION IS ADAPTED TO EXERT A COMPRESSIVE FORCE ON ASTRIP BEING ROLLED IN THE AREA OF SAID CORNER, SAID FORCE HAVINGCOMPONENTS BOTH PARALLEL AND NORMAL TO THE AXES OF SAID SHAFTS.